Air purge

❋❋Be sure that all valve cocks are closed.

ffThe air in the indoor unit and in the pipe must be purged. Make sure to vacuum inside of the connection pipe using vacuum pump after connecting pipes.(Use vacuum pump as shown at the figure.) If air remains in the refrigeration pipes, it will affect the compressor, reduce to cooling capacity and could lead to a malfunction.

1.Connect each assembly pipe to the appropriate valve on the outdoor unit and tighten the flare nut.

2.Connect the charging hose of low pressure side of manifold gauge to the packed valve having a service port as shown at the figure.

3.Open the valve of the low pressure side of manifold gauge counter-clockwise.

4.Purge the air from the system using vacuum pump for about 10 minutes. -- Close the valve of the low pressure side of manifold gauge clockwise. -- Turn off the vacuum pump.

-- Make sure that pressure gauge show -0.1MPa(-76cmHg) after about 10 minutes. -- This procedure is very important in order to avoid gas leak.

-- Remove the hose of the low pressure side of manifold gauge.

5.Set valve cork of both liquid side and gas side of packed valve to the open position.

6.Mount the cap and the needle valve cap to the valve (see the below illustration), and tighten them at the torque of 183kgf•cm with a torque wrench.

7.Check for gas leakage.

-- At this time, especially check for gas leakage from the 3-way valve’s stem nuts, and from the service port cap.

Gas pipe







Liquid pipe



Indoor unit








Liquid pipe side

Gas pipe side




Flare nut




Valve cock

Vacuum Pump



3-way valve

3-way valve







Needle valve


Outdoor unit










2015-03-03 오후 4:39:47